Open pit and underground mines that are developed beneath the groundwater table typically need to be dewatered. Dewatering is required in order to minimize water inflow to the operations, reduce operating costs, improve geotechnical performance of the mine, and create a safe working environment. Vertical pumping wells may be used in order to lower groundwater heads in advance of mining operations, and, in some cases, lower gravity flow in horizontal drains drilled into the mine walls from a surface within the mine.
However, vertical pumping wells are often difficult to implement and maintain for several reasons, including: (1) bedrock hydrogeology may be compartmentalized by sub-vertical faults and contacts, which may result in individual wells having limited hydrogeologic influence and productivity; and (2) wells may need to be placed directly within mine operating areas such that they may be destroyed or damaged by the advancing mine resulting in down-time of the dewatering system and frequent replacement and/or repair.
There remains a need for a mine dewatering system and method capable of removing water from mine areas in an efficient and cost effective manner.